using System;

class Secuqence
{
    static void Main()
    {
		//Write a program that prints the first 10 members of the sequence: 
		//2, -3, 4, -5, 6, -7, 8, -9, 10 ,-11 ...
		int positiveNumber = 2;
		int negativeNumber = 0;
		int seq = 2;
		Console.Write(seq);
		for(int i = 0 ; i<9 ; i++)
		{
			if(seq>0)
			{
				positiveNumber=positiveNumber+1;
				seq = positiveNumber * (-1); 
				negativeNumber = seq;
				Console.Write(" "+negativeNumber+" ");
			}
			else
			{
				positiveNumber = (seq * (-1)) + 1;
				Console.Write(" "+positiveNumber+" ");
				seq = positiveNumber;
			}

		}
    }
}
